Some of them ran toward the shots to get a glimpse of the gunman. Others came across shooting victims, both dead and alive.
These are their stories, as told to five Salt Lake Tribune reporters at the scene:
Jeremy Jensen, 26, of Salt Lake City, at Desert Edge Brew Pub, said he saw the shooter several hours earlier walking through the brewery. He remembered his long tan trenchcoat and that he had a mullet midway down his back. He said he was acting "a little weird. He kind of looked lost. I was about to ask him if he needed help."
The man entered the mall from the parking deck, carrying a shotgun, Jensen said. He saw a man run after spotting the gunman. The shooter turned and fired at him but Jensen could not see if the man was hit. "I saw the fire come out of the gun."
After that, Jensen heard a gunshot every 30 seconds for several minutes.
Ron Mason and DeEta Barta, of Salt Lake City, said they were eating at the Desert Edge when they saw a man coming in from the west parking lot.
The man, wearing a dark trench coat, carrying a long rifle or shotgun.
They saw him approaching and yelled, "There's a man with a gun!"
A few seconds later, they heard about 12 rounds.
Mason and Barta, who are registered nurses, went to assist the victim, a younger man who had suffered superficial gunshot wounds to the right temple and ear.
Though the young man was clearly in shock, the couple said, he told them that he saw his father go down.
A woman on the lower level of the mall, near the Black Chandelier store, said she heard a shot and looked up upstairs and saw the gunman. He had a long dark coat, dark brown hair and was carrying a rifle or shotgun, she said.
Brad Merrill was outside the Old Spaghetti Factory on the mezzanine when he heard a loud noise and the sound of glass breaking.
"All of a sudden, someone barged into the mall with a big shotgun," Merrill said. He was holding it in one hand, barrel up.
Merrill grabbed his young son and ran outside the mall, becoming separated from his wife and three other children.
As many as two-dozen shots were fired and he called 911.
Merrill said he believes the glass he heard breaking was the west door of The Sharper Image.
He called his wife and learned they were hiding inside a storage room inside the Sharper Image. They got out about 7:50 p.m.
Cedric Wilson, an employee at Rodizio Grill, was in the dining room when he heard two shots. He ran outside the restaurant onto the top level of the mall to see if anyone was hurt.
He looked down into the mall and saw a man with a long gun.
"I looked down and I saw him and he shot at [someone]," Wilson said.
The man turned to Wilson and fired twice. A projectile grazed his head, leaving about an inch-long track atop his short-cropped hair.
"I dropped to the ground as soon as I heard the shot."
Matt Lund, 44, said he heard a police officer identify himself and order the gunman to put his weapon down.
"There was a pause, a shotgun blast and then a barrage of fire," said Lund, whose wife Barbara Lund, owns the Secret Garden.
The couple hid in a storage closet in the store. When he left the closet and went into the mall hallway, Lund saw shotgun shell casings "scattered all over the floor and lots of broken windows."
Lund said he also saw a female victim face down and a male victim in the main corridor.
Shaura Cole was in the center of the mall area and saw a teenage boy in a white shirt and dark pants, lying on the floor with a gunshot wound to his head. She thought he was about 16.
The police and paramedics kept running up to him and looked down at him. It was clear they knew he was dead, Cole said.
A girl with a pink shirt ran to the boy, crying, fell to her knees and started shaking him. She was taken away by police a short time later.
John and George Donham, who live in an apartment south of Trolley Square, were walking through the east parking lot of the mall when they heard gunshots.
They saw several women running out of building then saw a man sitting in the passenger side of a dark Chrysler 300, bleeding from a head wound.
John Donham said one side of the man's head looked like "meatloaf" and appeared to be in shock.
The victim said, "That guy's in there just shooting."
He told the Donhams that he had been shot while he was on the second floor main lobby on the north side of the mall.
The Donhams, who took cover behind a car, said they heard at least five more shots before officers arrived.
The men said they saw five or six officers run toward the mall with guns drawn. They tried to call the officers' attention to the shooting victim in the car, but the officers said, "We've gotta go in and stop this killer," the Donhams said.
The cops ran in and then the Donhams heard multiple gunshots.
The victim said, "Please get me to a hospital. Please get me to a hospital," said George Donham.
The Donhams said two women came upon the scene and told them that the gunman had walked into the Desert Edge Brew Pub and opened fire.
Lindsay Sharifi, 26, her sister, two young nieces and mother were together in the Basket Loft when a man and woman ran in saying a man was shooting.
The store owner ran and locked the store door and turned out the lights Everyone inside ran back into a small storage space. Eight in all, they stood and prayed together for about 90 minutes.
They heard the gunman going into each store, one by one, getting closer to the store they were in. They heard a lot of screaming and gunshots that sounded like plywood falling to the ground.
A SWAT team eventually ordered everyone out with their hands up.
In a trading card store next to the Basket Loft, Sharifi and her party saw three bodies on the floor and glass everywhere.
"We were all being quiet, trying to figure out, 'Where is he?' " said Sharifi. "We didn't know if he was going to come in and kill us all."
Clifton Black, 26, and Melinda Gurr, 21, of Salt Lake City, listened to the shots as they hunkered down in the back of the Black Chandelier, a clothing store.
The shots started slowly, then they became rapid.
A 17-year-old female clerk turned off the lights of the store and locked the front doors. She and Black and Gurr then hid until the gunfire stopped.
They then ventured to the front window, where they caught the eye of a sheriff's deputy who was carrying a shotgun.
He shouted, "Two civilians," and told them to walk to the exits with their hands over their heads.
On their way out of the mall, they saw a "heap of bodies" in one of the stores, Black said. The injured people were being treated by paramedics, he said. They saw at least one other man on the ground while leaving the mall, he said.
At 7:30 p.m., police were still staged outside the mall with guns drawn, as if another shooter was on the loose.
Carol Steffens, 56, Salt Lake City, was hiding inside a restaurant while the gunman was shooting up the mall.
She and her boyfriend had taken a friend who was visiting from Albuquerque out to eat at the Desert Edge Pub.
But after they had sat down and ordered, about 6:40 p.m., they heard "a boom."
They thought it was a noise from the kitchen, but many people were moving toward the restaurant's exits "with looks on their faces of 'let's get the hell out of here.' Then we heard another boom and knew somone was shooting something."
Then people in the restaurant began running all over the place.
Steffens said she and her friends first sought sanctuary in the bathroom, then left intent on exiting the building through east stairway.
While on the stairs, the people trying to leave stopped en masse.
"You could hear the gunshots, like a shotgun," she said, "You could hear that it was fairly close."
She, along with others on the stairs, ran back up the stairs and hid in the bathroom.
"There were seven women and one guy," in the bathroom, she said. At this time, Steffens became separated from her girlfriend and boyfriend, who had escaped the mall from the west stairway.
Over a 10- to 15-minute period, Steffens said she heard about 10 more shotgun shots and then six shots that sounded like they came from a smaller gun.
"We waited," she said, and contacted her boyfriend and girlfriend on her cellphone. They were safe in their car in the parking garage.
Then an employee came and told the group in the bathroom to get out, and they exited the mall through the west entrance.
She met up with her friends in their car, and they drove from the mall.
"I was really scared because the gunshots . . . were loud, they sounded like they were coming from underneath the restaurant," she said.
"We just feel so fortunate that we got out. It's just a tragedy. We feel very sad for those families that have lost family members there," Steffens said.
Barrett Dodds, 29, saw a police officer shoot the gunman, according to the Associated Press. Dodds, who was working at the Brass Key, exited the antique store after hearing several shots. He ran into a man who identified himself as an Ogden City police officer.
It was difficult to tell where the shots were coming from, but Dodds directed the officer to the lower level where he believed the shooter was.
He said he got a good look at the gunman and watched as the gunman reloaded several times and shot.
"I was trying to find something to throw at him [the gunman]," Dodds said.
Dodds watched the suspect exchange gunfire with the officer outside a card store, the AP reported. The gunman, he said, was backed into a children's clothing store.
''I saw the cops go in the store. I saw the shooter go down,'' Dodds told the AP.
* NATE CARLISLE, LISA ROSETTA, MICHAEL N. WESTLEY, MATTHEW D. LAPLANTE and RUSS RIZZO contributed to this story